1. Field of the Invention
The present invention relates in general to a recording head, and more particularly to a recording head configured such that external signals are inputted thereto using a flexible wiring member, and to methods for manufacturing and inspecting the recording head.
2. Discussion of Related Art
As a recording apparatus configured to perform recording by ejection of ink from a recording head onto a recording medium, there has been known a recording apparatus disclosed in a Patent Document 1 (JP-A-2002-160372, in particular, FIGS. 4 and 6). In the disclosed recording apparatus, an external signal source and the recording head are connected to each other by a flexible wiring member on which is mounted a drive circuit, and signals supplied from the external signal source are inputted to the recording head via a drive circuit, so that the ink is ejected selectively from nozzles of the recording head, thereby performing the recording.
In a case where an actuator included in the recording head is, for example, a piezoelectric actuator as disclosed in the Patent Document 1, etc., voltage for polarizing may be applied to the piezoelectric actuator using the flexible wiring member after the flexible wiring member is connected to the piezoelectric actuator, thereby polarizing portions of a piezoelectric layer of the piezoelectric actuator which are to function as operable portions.
More specifically described, there are provided a shift register, a D flip-flop, a driver, etc., in the drive circuit mounted on the flexible wiring member disclosed in the Patent Document 1. The flexible wiring member includes conductor wires (i.e., lines) VDD1, VSS1, VDD2, VSS2 that are connected to the drive circuit. The conductor wires (i.e., lines) VSS1, VSS2 are connected to a common voltage portion of the drive circuit, and are normally grounded. Further, the flexible wiring member includes a conductor wire (i.e., line) VSS3 which is commonly connected to a common electrode (a common voltage portion) of one of piezoelectric deformable portions (each as the operable portion).
When polarizing, in a manufacturing process, the piezoelectric actuator of the recording head which has been assembled, a device constituted by a circuit and a power source (that are equivalent of a circuit and a power source that are used for ejecting the ink) is connected to the conductor wires VDD1, VSS1, VDD2, VSS2, etc., of the flexible wiring member, and a polarizing device is connected to the conductor wire VSS3. Then, voltage of V1 is applied from the conductor wire VDD2 to the operable portions of the actuator via the drive circuit, and in addition, minus voltage V2 is applied to the conductor wire VSS3, so that total voltage of (V1+V2) is applied to the operable portions, thereby polarizing the piezoelectric actuator. When the ink ejection is performed after the polarization has been completed, the conductor wires VSS2, VSS3 are connected to each other via another conductor wire so as to be kept at almost the same voltage with each other, e.g., at zero voltage or a ground.
In a case where the flexible wiring member is connected to the piezoelectric actuator by soldering after the piezoelectric actuator has been polarized, a polarized condition of the piezoelectric actuator may be deteriorated due to a heat generated by the soldering. However, in the recording apparatus disclosed in the Patent Document 1, the polarization is performed after the flexible wiring member has been connected to the recording head, thereby maintaining a good polarized condition of the piezoelectric actuator.